348636-04-4

Upstream product

• 131489-59-3 (E)-methyl-4-(N-benzylamino)-but-2-enoate 
• 348636-14-6 1-(4-Chloro-2,6-dimethoxypyrimidin-5-yl)ethanone 
• 100-46-9 benzylamine 
• 1117-71-1 methyl-4-bromo-2-butenoate 
• 134221-49-1 1-(6-Chloro-2,4-dimethoxypyrimidin-5-yl)ethanol 

Downstream Products

• 348636-03-3 9-Benzyl-2,4-dimethoxy-7-(2-methoxy-2-oxoethyl)-5-methyl-8,9-dihydro-7H-pyrimido[4,5-e][1,4]diazepin-6-ium-6-olate 

Relevant academic research and scientific papers

Pyrimidine annelated heterocycles-synthesis and cycloaddition of the first pyrimido[1,4]diazepine N-oxides

5-Formyl- and 5-acetyl-4-(alkenylamino)pyrimidines 5 have been prepared as precursors to novel pyrimido[1,4]-diazepine N-oxides 3. In addition to cyclisation to the targeted dipoles the substrates 5 have also been observed to form imidazopyrimidines 12 and 39 via an intramolecular Michael addition; additionally 5b has been observed to form the pyrimidoazepinone 42. Aldonitrone 3a cycloadded readily to olefinic dipolarophiles; ketodipole 3b did not share this reactivity. Both dipoles reacted with acetylenic dipolarophiles but the ensuing cycloadducts 37 were unstable; facile ring contraction of their isoxazolopyrimidodiazepine skeletons to the pteridine nucleus is noted. The structure of 37c has been determined by X-ray crystallography.